let path = require('path')
let mypath= ''

let x = path.extname(mypath) //获取文件后缀名
console.log(x)
let y = path.parse(mypath)//序列化路径 返回一个对象
console.log(y)
let z = path.basename(mypath)//返回path最后一个部分
console.log(z)
let v = path.dirname(mypath)//返回目录名
console.log(v)